Inovonics 235, Operating And Maintenance Instruction Manual

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emPOWERs the operator of the Processor to reach new
heights in broadcasting sustainability . (?)
PROCESSOR SETUP PROCEDURE
This setup procedure assumes a typical, transmitter-site installation of
the 235, with the LINE INPUT fed from the output of the console or from
a telephone line or STL receiver.
At this point the Processor should be installed in the program chain
with power applied. The OUTPUT LEVEL control should be turned fully
counterclockwise.
Input Level
Adjustment
The INPUT GAIN control is adjusted to center the AGC operating range
with a nominal “Zero-VU” program line input. If the following
procedure shows control range to be outside adjustment limits, recheck
circuit board jumpering for Input Gain Range selection as described on
Page 9.
1. Apply a 500Hz test tone from the console at a level one-and-one-
quarter dB above normal reference level. This is simply a console
VU meter indication of +1¼VU.
2. Adjust the
INPUT GAIN
control so that both the 0dB
AGC GAIN
indicator and the one just below it (–2.5dB) light equally.
Remember that the AGC circuit responds very slowly to level
change, so exercise patience in making this important adjustment.
Once the INPUT GAIN has been adjusted with a test tone, you can
switch-over to normal program material. If the procedure has been
performed properly, and if the board operator pays reasonable
attention to the meter, AGC GAIN will nearly always remain between
+5dB and –5dB.
Output Level
Adjustment
Perform this part of the setup procedure “on air” under normal
operating conditions and using typical program material. You must
have access to the station’s Modulation Monitor and understand its
operation.
1. Preset panel controls as follows:
OUTPUT LEVEL — fully counterclockwise
POS. PEAKS — fully counterclockwise
EQUALIZATION — 0dB
for both
HIGH FREQ.
and
LOW FREQ.
PROGRAM DENSITY — (MAX)
PEAK PROCESSING — (MAX)
2. Advance the OUTPUT LEVEL control for negative peak modulation
of 90% to 95% as indicated by the Mod-Monitor.
3. If permitted by local regulations, advance the POS. PEAKS control
for positive peak modulation of as much as +125% as indicated by
the Mod-Monitor.